PPRuNe Forums - View Single Post - Inverted, unloading and reducing angle of attack on Modern Jet Aircraft
Old 23rd May 2017, 08:19
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H Peacock
 
Join Date: Sep 2004
Location: Yorkshire
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I assume you mean inverted with a positive AoA, ie similar to the top half of a loop. If the nose is still above the horizon you could unload then roll wings level, but you'll invariably be decelerating throughout - so you'd need to have plenty of speed first to avoid running out (stalling). Better to wait until the nose is just below the horizon prior to gently unloading and then rolling wings level. In the latter case the speed will either gently increase or even remain stable. Of course if the nose is already well below the horizon (speed rapidly increasing and g load increasing) you'll need to be more aggressive with the unload prior to rolling wings level. Selecting idle power and perhaps a tad of spoiler might help control the speed, but it's now a careful balance between pulling too hard and overstressing the aircraft or not pulling enough and overspeeding the aircraft. Of course the latter assumes you're well clear of the ground so not a factor. Do you really need to pull 3.5g when say 2.5g may suffice?

Depending upon the trim settings, the unloading may be a relaxation of the pull or indeed a positive - but gentle - push.
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